A torque transmission assembly includes a driving shaft, a driven shaft, and a coupler to connect the driving shaft to the driven shaft, such that the driven shaft rotates together with the driving shaft. The coupler typically includes a first coupling member and a second coupling member. The first coupling member includes a base to be connected with the driving shaft, and a plurality of arms extending axially from the base. The arms of the first coupling member are spaced with a gap formed between each two neighboring arms. The second coupling member includes a base to be connected with the driven shaft, and a plurality of arms extending axially from the base.
When assembled, the arms of the second coupling member are received in the gaps of the first coupling member and abut against the arms of the first coupling member in a circumferential direction of the coupler. Therefore, torque can be transmitted from the driving shaft to the driven shaft by the coupler. However, the first coupling member and the second coupling member both have a base which adds length to the coupler. As a result, it is difficult to miniaturize the torque transmission assembly.
Therefore, there is a desire for an improved coupling device that can overcome the above described shortcomings.